<span>d = r*t
t = hours at 20 mi/hr
20t + 12*(4.5 - t) = 70
8t = 16
t = 2 hours
d at 20 mi/hr = 20*2 = 40 miles
40/20 + 30/12 = 4.5 hours
Fiora travels a total distance of 4.5 hours</span>
Answer:

Explanation:
We can solve the problem by using the following suvat equation:

where
v is the final velocity
u is the initial velocity
a is the acceleration
s is the displacement
For the car in this problem:
u = 0 (it starts from rest)
is the final velocity
s = 10 km = 10 000 m is the displacement
Solving for a, we find:

When going round a corner your direction changes which means your velocity changes which means there is an acceleration.